CACOSH(3) Linux Programmer s Manual CACOSH(3)

NAME cacosh, cacoshf, cacoshl - complex arc hyperbolic cosine

SYNOPSIS #include <complex.h>

double complex cacosh(double complex z); float complex cacoshf(float complex z); long double complex cacoshl(long double complex z);

Link with -lm.

DESCRIPTION The cacosh() function calculates the complex arc hyperpolic cosine of z. If y = cacosh(z), then z = ccosh(y). The imaginary part of y is chosen in the interval [-pi,pi]. The real part of y is chosen non-neg- ative.

One has:

cacosh(z) = (0.5) * clog((1 + z) / (1 - z))

VERSIONS These functions first appeared in glibc in version 2.1.


SEE ALSO acosh(3), cabs(3), cimag(3), complex(7)

COLOPHON This page is part of release 3.22 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at

2008-08-11 CACOSH(3)